Princess Magar Sepora is the last person in the five kingdoms with the ability to create a magical glowing element with her own body. In her home, her father values her only for this ability -- it is what their country relies upon for trade, and what they will need in the war he's starting with their long time rival country. But Sepora is done with this -- she will not finance a war, and sees no option but to fake her own death and go into hiding in the country her father hopes to destroy. Here she can blend in with the descendants of slaves that were stolen from her own home generations before. Here she can keep her secret and all the kingdoms must learn to get by without the magical element she created for so long.
Tarik must begin his rule of the neighboring country after his father dies of an illness that's sweeping the city. People are dying quickly, and Tarik knows that have only an uneasy peace with the other kingdoms. His advisors encourage him to stay with tradition and rule the way his father did. Tarik knows that this isn't the best way, and that things must change.
Nemesis is told in chapters alternating between Tarik and Sepora's viewpoints. They start out separate, though, obviously, the two stories merge. The general plot and the romance are fairly predictable, but the world Banks' creates is new and exciting. Sepora and Tarik are both strong, smart characters, and though certain parts are no surprise, it's still fun to read how the characters get to each point, and the discoveries they make in their world along the way.